That's a good catch. I don't know offhand when it changed, but during the antebellum period a lot of political power was routed through the SC General Assembly. Eligible white male voters could vote for their state representatives, but the legislature would then choose the governor and other prominent state positions, US senators and representatives, and vote on the state's behalf for President.

What's fascinating is how this reflects upon South Carolina's (though the South was indeed diverse, SC wasn't singular in its beliefs either) interpretations of American notions of liberty and republican government. They were adamant in their support of these ideas but were also forced to reconcile them with their wider cultural beliefs which espoused the existence of naturally elite men (and they were men) who were uniquely suited to lead the rest of society. These men distinguished themselves through social, personal, and economic independence as demonstrated through ownership of land and slaves as well as absolute control of their business (plantation) and family lives. They achieved economic independence via prosperous plantations and demonstrated leadership through the control of dependents (wives, children, slaves). Theoretically any white man could enter this class but SC's commitment to this ideal also meant that state government was highly insular and restrictive. A small elite group kept a firm grip on nearly all state government affairs.

Readings:

Stephanie McCurry, Masters of Small Worlds

Drew Faust, James Henry Hammond and the Old South